olsen



J. c. OLSEN Re. 21,475

SEAL

Original Filed Oct. 12, 1933 Reissued June 4,1940

sum

PArsNr-i OFF-ICE SEAL John 0. Olsen, Chicago, 111., asslgnor, by memeassignments, to Chicago Rawhide Manufacturiinlfn Ogmpany, Chicago, 111.,a corporation of Original No. 2,093,021. dated serum 14. 19:1.

Serial No. 693,255, 0mm 1:, 1m. Application for reissue August 21, 1939,

Serial so.

is cum (on asss) This invention relates to improvements in seals, andmore especially, but not exclusively,

seals for rotatable shafts, commonly called oil seals.

In oil seals for shafting, it is well recognized that, where a flexiblepacking such as leather is employed, the packing should have a uniformpressure engagement with the shaft around the entire circumference andthat this pressure [0 should be relatively light so as'to obtaina'feather-like" touch, particularly in the zone of the. free edge of thepacking that engages the shaft.

Especially is the, uniform but feather-like pres-' sure important whenemployed with shafts rotating at relatively high speed in order to pre-'vent scoring of the shaft and also to minimize friction and generationof heat.

Heretofore, many expedients have been employed with packings and moreparticularly leather packings or washers for exerting the constrictingpressure around the shaft such as garter springs, metallic spring discswith slit flngers and the like. Such expedients, however, havenot provenentirely satisfactory, and have 4 had limited scope of usefulness,particularly as respects high speed shafts, primarily on account of theinability to maintain continuous uniform pressure around the shaft andinability to compensate for any eccentricity that may be 0 developed inthe shaft under high speeds. Such former types of seals have also almostuniversally employed a leather washer having an axial sleeve section anda radial flange section with the latter clamped, as a result of whichstresses are un-' 5 avoidably set up in the washer, due to the sharpangular bend therein, which militates against the desired flexing of thesleeve portion in accommodating itself to anyslight eccentricities ofthe shaft.

D One object 'of this invention is to provide a seal for preventing thepassage or leakage of oil or other lubricant, water or other foreignmatter, lengthwise of a shaft and wherein is employed a flexiblepacking, preferably leather, having as- 5 sociated therewith contractilepressure means to maintain the seal joint not only uniformly andcontinuously completely around the shaft, but over an appreciableextended width or none lengthwise of the shaft adjacent the free'edge ofthe packing, the contractile pressure means being further characterizedin that the pressure therefrom may be delicately regulated so as tominimize friction and possibility ofsccring and equally effectivewitheither slow speed or relatively high speed shafts.

Another object of the invention is to provide a seal of the characterindicated in the preceding paragraph so arranged that the contractilepressure means, considered asan entirety, is adapted .to .float freelyin a radial plane so as to insure maintenance of the uniformity ofcontractile pressure on the washer in any position of the shaft relativeto the casing of the seal, regal-d less of whether the shaft occupies anexact axial position withreference to said casing or has an eccentricmovement within tolerated limits when under rotation. r A further objectof the invention is to provide an oil seal embodying a floatingcontractile pressure means or unit as indicated in the precedingparagraph combined with a flexible washer so formed and attached to theoil seal casing, that the' washer is free from the usual right angularradial clamping flange and resultant stresses tending to stiffen it,.tothe end that the washer itself is freely flexible or adjustable inaccordance with any eccentric movements of the shaft to the end that thearea of contact between the washer and shaft isFalways maintaineduniform.

Other objects of the invention are to provide an oil'seal which may beeconomically manufactured and assembled; which may be sold, shipped andapplied completely assembled as a unitary article; and in whichprovisionis made in the construction and assembling of the .parts toinsure absolute accuracy of the relative intended positions of the partsof the unit.

Other objects ofthe invention will more clearly appear from thedescription and claims hereinafter following.

In the drawing forming a part of this specification, Figure 1 is avertical, diametrical, sectional view showing a seal embodying theimprovements in position relative to a rotating shaft, a portion of thelatter being indicated. Figure 2 is a transverse, vertical, sectionalview corresponding substantiall;,' to the line 22 of Figure 1. AndFigure 3 is an enlarged, radial sectional view correspondingsubstantially to the line H of Figure' 2. v a

In said drawing, a portion of a shaft is indicated at III with which theimproved seal is adapted to cooperate,the improved seal comprisingbroadly, a sheet metal casing A; a packing or washer B; a washerclamping ring 0; a floating contractile spring pressure unit designatedgenerally by the reference D; and a locking ring E for the floatingpressure unit D. I

The shell or casing A is preferablycomprised of a drawn cup shaped sheetmetal member having an outer annular rim II and a radial flange ii, thelatter being apertured as indicated at I! so as to freely receive theshaft therethrough. As will be understood, the peripheral section II ofthe casing will be made of such shape, usually cylindrical, and size asto permit of a friction drive flt within the usual recess of the shafthousing and provide a sealed joint therewith. At its free edge,the-peripheral section II is rabbeted so as to provide an inner shoulder45 against which is seated the other section comprising the othermemberof the casing which is more or less in the form of an annular discll, having an inturned annular flange l5 encircling the shaft and havingan interior diameter slightly greater than thediameter of the shaft. Thecasing member I is assembled with the other casing member against theshoulder 45 and the edge of the cup shaped member squeezed down so as torigidly and permanently unite the two casing members. In thisconnection, it will be observed that by providing a shoulder 45,absolute uniformity of the spacing between the' radial walls I! and llof the casing is assured and consequently accurate positioning of theother parts within the casing assured. Particular attention is directedto the formation of the intumed flange l5. In-

;itially said flange is made of the same thickness as the radial washersection I4 and is formed with its inner diameter approximately equal tothe diameter of the shaft tobe entered therethrough. The flange is thenbored so as to enlarge the axial shaft opening to provide the necessaryclearance for the shaft in allowing for any oif positioning or eccentricmovements thereof. As obvious, this will result in a thinning of theflange Iii so that the outer diameter of the latter remains as small asconsistently possible with the structural strength required of thecasing. The purpose of maintaining the outside diameter of the inturnedflange I! at a minimum is to allow of the washer B being seated andsealed thereon with a minimum stretch or expansion of the clamped end ofthe washer and to bring the clamped section of the washer B as nearly inline as is possible with the free sealing edge thereof, as will beobvious from inspection of Figures 1 and'2. In this connection thedrawing illustrates a seal for a two inch shaft wherein Figures 1 and 2are twice the scale of the actual seal and Figure 3 is substantiallyfour times the actual size. In actual practice, the inside diameter ofthe flange I! will be approximately 23 5" for a two inch shaft and thethicknessof the flange it one sixteenth of an inch, so that the outsidediameter of the flange is 2 For shafts of other sizes, the seals willhave proportionate dimensions, as will be'understood. The washer 13,preferably of leather, is of substantiallycylindrical form except forthe slight stretching or expansion necessitated where the clamped end i6thereof is seated over the flange l5, thus minimizing any internalstrains within the washer and providing for the maximum flexibilitythereof and particularly the capacity of the free or sealing zoneportion H to float with the shaft. The clamping edge I. of' the washeris seated over the flange I! as previously described'and is clampedthereon by an angular ring C pressed thereover'with a tight frictionflt,

said ring C being preferably of'angular cross section as shown. Toadditionally secure the washer, the flange II is outwardly pressed atsuitable spaced intervals therearound, as indicated at It,

lubricant coming from the left. ,Heretofore so far as aware, noattention has been paid to the formation of the edge of the sealingwasher. By beveling the same in the manner shown and described, pressureexerted in the zone of the free edge, while tending to compress thewasher, cannot, however, result, in any separation of the inner corneredge, indicated at ISI from the shaft, which is a defect inherent inprior types of seals. Should a gap between the free corner edge Isl ofthe washer and shaft occur, experience has demonstrated that the oilwill get within said gap and gradually continue to work its waylengthwise of the shaft even between the-sealed line of contact,presumably due to a squeezing action repeatedly closing up such gap.With the present construction shown, this danger is reduced to aminimum.

The floating pressure unit 1) comprises a floating metallic ring 20,.and a plurality of arcuate pressure members 2l-2l, each havingassociated therewith a spring 22. The ring is preferably in the form ofa drawn cup shaped member having an annular flange 23 and radial flange24,

the latter being centrally apertured as indicated at 25 so as to providethe necessary clearance for the washer B, which is extendedtherethrough. The outside diameter of the flange I3 will be made such asto allow for movement of the ring in a radial plane within toleratedlimits of eccentricity of the shaft, as will be understood.

Each of the pressure members II is preferably made of sheet metal formedwith suitable dies, each said member having a radial web II and anarcuate inner flange 21, the interior diameter of the lattercorresponding to the exteriordiameter of the washer with whichassociated. Ateach end, the web section II is provided withlongitudinally arranged small flanges 2. extending in. the samedirection as theflange I], said flanges 28 movement of the pressuremembers I! will be limited by the radial shoulders 28 coming into contact with each other, thereby preventing collapsing of the washer evenwhen impregnated with oil and soft and facilitating application of theseal to the shaft under all conditions. Out-' wardly'of the shoulderflanges 28, each pressure member if at each end thereof is cut back andformed with spring attaching flanges "-20, notched top and bottom asindicated at 30-" to receive and retain in position the hook shaped ends32 of the springs 22.- which are engaged thereover. At the cenfer'of itsouter edge, each pressure member 2i also has struck up therefrom,smoreor less triangular flange It suitably notched to receive thewire'spring 22 as indicated at 34 whereby, as will be apparent,eachspring 22 is maintained in proper position with reference to itspressure element 2|.

Each spring 22 is of relatively light spring wire and, when in place inoperative position, of generally arcuate form on a radius. somewhatgreater than the outer radius of the pressure member so that eachspring, at the ends of the arcuate portion proper, will have shoulderedengagement, as indicated at 3535 with the peripheral flange 23 of thefloating ring, resulting in an equalized centrally applied pressure tothe pressure member through the bearing shoulder 33. With thisarrangement, it will be further observed that each pressure element 2|is adapted for individual rocking or angular adjustment with referenceto its spring so that the pressure elements may readily adapt themselvesto the washer and insure uniform pressure throughout the arcs ofcontact. Further, by forming the springs in the manner shown anddescribed, the spring pressure may be made very light and accuratelycontrolled since even an appreciable outward radial movement of onepressure element 2| with respect to the floating ring 20 will induceonly a relatively slight additional flexing of the long are of thespring 22.

' Referring to Figures 1 and 3, it will'be observed that the innerarcuate flanges 21 of the pressure members are of appreciable width orextent lengthwise of the shaft and that the same are extended slightlybeyond the free edge of the washer and also overlie the edge zone of thelatter for an appreciable distance so as to insure a rel atively wideband or zone of contact between the pressure elements and the washerwhich in turn insures a correspondingly wide band or zone of J surfacecontact between the washer and the shaft. With this arrangement, arelatively feather-.like pressure may be maintained on the washer and,on account of the wide band of sealing contact between the latter andshaft, an exceedi ngly effective and eflicient seal is obtained withoutdanger of scoring or generation of excessive heat. It will further beobserved that not only is each pressure. element 2! independentlyadjustable but that the entire set of pressure elements floats or isadjustable in their entirety in a radial plane so that even in aneccentric position of the shaft, the uniformity of pressure around theentire circumference of the washer will be maintained ascontra-distinguished from any arrangement where the spring pressureisexerted between a pressure element and the fixed wall of a casing where,in an eccentric position of the shaft, pressure elements to one sidewould be under increased spring pressure and those on the other sidewould be under decreased spring pressure.

The floating pressure unit D is maintained in proper position by meanscf the spring wire ring E, which is sprung into place in an annulargroove 31 formed on the interior of the casing section II, said ring Ebeing so located that the floating ring 20 may move relatively freelywithout, however, permitting it to shift unduly in an axial direction.Inasmuch as the washer B is positively held against rotation by theclamping ring C and lugs ill, the floating pressure unit D will beretained against rotation within the casing.

In the drawing, six pressure elements and associated springs are shownwhich will preferably be the number used for a two inch shaft seal. Aswill be understood, howeve the number of said pressure elements may bevaried, the essential 3 feature being that they shall be arranged in acircular series so as to'provide a substantially cates otherwise.Furthermore, the improved seal has been described with particularreference to preventing the passage of oil or lubricanttherethrough butit is obvious that the seal is effective for preventing the passagetherethrough of any liquid or semi-liquid or foreign matter generallysuch as water and dust.

Although the preferred manner of carrying out the invention has hereinbeen shown and de-- scribed, the same is merely illustrative and allchanges and modifications are contemplated that come within the scope ofthe claims appended hereto.

What is claimed is: a 1. A seal for a shaftrotatable within a relativelyflxed housing, said seal comprising: a generally annular metallic casinghaving an outer peripheral wall, axially spaced side walls apertured forthe accommodation of a shaft there? through, one of said walls having anintegral circular flange extending axially inwardly of the casing and ofslightly greater inside diameter than the shaft to be accommodated; aone piece 'flexible packing having a shaft-engaging sleeve section atone end and an enlarged circular section at the other end encirclingsaid circular flange and sealed therewith; and means for yieldinglyconstricting said sleeve section of the packing to provide a sealedjoint with the shaft, said means including a circularly arranged seriesof pressure elements and spring means coacting therewith.

, 2. A shaft seal comprising: a generally annular metallic casing havingan outer peripheral wall, axially spaced side walls apertured for theaccommodation of a shaft therethrough, one of said walls having anintegral circular flange extending axially inwardly of the casing, saidflange being of slightly greater inside diameter than the theft to beaccommodated and of reduced thickness relative to the wall with which itis integrally formed to provide a minimum'outside diameter; a flexiblepacking having a shaft-engaging sleeve section at one end and a slightlyenlarged circular section at the other end to flt over said flange;

means, separate from the casing and encircling said circular section ofthe packing, for sealing said circular section with said flange; andmeans yieldingly constricting said sleeve section of the packingtoprovide a sealed joint with the shaft.

3. A seal of the character described comprising: a casing having axiallyspaced side walls apertured for the accommodation of a' shafttherethrough; a flexible packing within the cas-z ing clamped with asealing engagement thereto, said packing having a shaft-engaging sleevesection; and means for constricting said sleeve section in the zone ofits free edge comprising: a floating carrier and a pluralityofindependent, spring-influenced pressure elements carried thereby, saidelements surrounding the packing and engaging therewith and all of saidelements being movable as an entirety with said carrier.

4. A seal of thecharacter described comprising: a casing having axiallyspaced side walls apertured for the accommodation of a shafttherethrough; a flexible packing on the interior of said casing andclamped thereto to provide a seal therewith, said packing having anaxial sleeve portion to engage the shaft; a plurality of circularlyarranged pressure elements encircling and engaging said sleeve sectionof the packing; a carrier within the casing movable in a radial planewith respect thereto; and spring means interposed between said carrierand pressure elements, all of the latter being bodily movable in unisonwith the floating carrier.

5. A seal of the character described, comprising: a casing havingaxially spaced side walls apertured for the accommodation of a shafttherethrough, one of said walls being provided with an inturned annularflange: a flexible packing of generally cylindrical form having one edgeportion thereof telescoped over said flange and sealed therewith, theother edge portion being adapted to engage the shaft; and a floatingpressure unit including a plurality of independent elements in acircular series within the casing having cooperative engagement withsaid sleeve section in the zone of the free edge of the latter.

6. A seal of the character described, comprising: a casing havingaxially spaced side walls apertured for the accommodation of a shafthaving one edgeportion engaged over and secured to said inturned flange;a plurality of independent circularly arranged pressure elementscooperable with the free edge of the sleeve section of said packing,said elements engaging the latter over a relatively wide band andextended also beyond the free edge of the packing; and spring meanscooperable with said pressure elements normally urging the latterradially inward.

'7. A seal of the character described, comprising: a casing havingaxially spaced side walls centrally apertured for the accommodation of ashaft therethrough, one of said walls having an integral inturnedannular flange of inner diameter slightly greater than the shaft to beaccommodated; a flexible packing of substantially cylindrical formhaving one edge portion engaged over and sealed with said flange, theopposite free edge of said packing being beveled inwardly.

\ gaging the free edge portion of said packing.

8. As an article of manufacture, a pressure element for an oil seal,said pressure element being of generally arcuate form with a radiallyextending web and an. inner arcuate flange, said element at each endthereof being provided with shoulder flanges and alsowith springretaining flanges, said element having a spring bearing flangeat itscenter on the outer edge thereof.

9. As an article of manufacture, a pressure element for an oil seal,said pressure element being of generally arcuate form with a radiallyextending web and an inner arcuate flange, said element having at eachend thereof a shoulder flange adapted to cooperate with a correspond.-

flange of an adiacent element, said element having also means thereonfor engagement with a spring. I

10. As an article of manufacture, a pressure element for an oil seal,said pressure element being of. generally arcuate form with ,a radiallyextending web and an inner arcuate flange, said element having anintegrally formed spring hearing flange at the center of the outer edgeof said web. i

11. A seal for a shaft rotatable within arelatively fixed housing, saidseal comprising: a gentured for the accommodation of ;a;sha,fttherethrough, one of said walls havingja circular-flange extendingaxially inwardly 'of the casing and of slightly greater inside diameterthan the shaft to be accommodated; a flexible packing having ashaft-engaging sleeve section at one end and an offset circular sectionat the other end, the latter section encircling said circular flange;means for sealing said circular section of the packing with saidcircular flange; and means for yieldingly constricting said sleevesection of the packing to provide a sealed joint with the shaft, saidmeans including a circularly arranged series of pressure elements and aplurality of springs coacting therewith.

12. A seal for a shaft rotatable within a relatively-fixed housing, saidseal comprising: a -gen erally annular metallic casing having an outerperipheral wall, axially spaced, radially extending side walls aperturedfor the accommodation of a shaft therethrough, one of said walls at itsinner edge having an integral cylindrical flange extending axiallyinwardly of the casing substantially parallel toand only slightly spacedfrom the shaft to be accommodated; a flexible packing having a shaftengaging sleeve section at one end and a relatively slightly outwardlyoffset cylindrical section at the other end embracing said cylindricalflange of the wall; means, separate from the casing and located betweensaid cylindrical section of the packing and said peripheral wall of thecasing, sealing said cylindrical section of the packing with saidcylindrical flange; and means yieldingly constricting said sleevesection of the packing to provide a sealed joint with the shaft.

13. As an article of manufacture, a floating constricting unit for ashaft packing adapted to be housed within a casing, said unitcomprising:

a metal ring of substantially right angle cross section with one flangethereof constituting the periphery of the ring and the other flangeextending radially inward therefrom; a circularly arranged series ofindependent sheet metal pressure elements slidably mounted on saidradial flange of the ring, each of said elements being also ofsubstantially right angle cross section with one flange extendingradially and the other of arcuate formation, the arcuate flanges beingadapted to engage the packing; and a spring interpoud between each saidpressure elementv and said peripheral flange of the metal ring.

14. A sea] for a shaft rotatable within a relatively flxed housing, saidseal comprising: a generally annular rigid casing having an outerperipheral wall and a radially extending side wall, which side wall isapertured for the accommodation of a shaft therethrough and is providedat flexible annular packing within said casing having a shaft-engagingsection at one end and an outwardly oflset section at the other endsleeved over and embracing said flange; and a separate rigid ringstructure which is positioned in the casing between said outwardlyoflset section of the packing and said-outer wall and is prowided with aclamping portion insubstantially spaced relation to said outer wall.which clamping portion is disposed in radially clamped engagement withsaid outwardly oflset section oi the packing at a point directlyopposite said flange, thereby fixedly holding and sealing said outwardlyoflset section with said flange.

15. A seal for a shaft rotatable within a relatively fixed housing, saidseal comprising: a generally annular rigid casing having an outerperipheral wall anda radially extending side wall, which side wall isapertured for the accommodation of a shaft therethrough and is providedat its'inner edge with an integrally formed inturned .flange whichextends axially "within the casing in substantially spaced relation tothe outer wall; a flexible annular packing within said casing having ashaft-engaging section at one end and an outwardly oiiset section at theother end sleeved over and embracing said flange in substantiallyflatwise engagement with the same; and a separate rigid ring structurewhich is positioned in the casing between said outwardly oflsetsectionot the packing and said outer wall and is provided with aclamping flange in substantially spaced relation to said outer wall,which clamping flange is disposed in radially clamped substantiallyflatwise engagement with said outwardly oflset section 0! the packingat' a point directly opposite and surrounding said inturned flange,thereby fixedly holding and sealing said outwardly oflset section withsaid inturned flange.

16. A seal for a shaft rotatable within a relativeiy fixed housing, saidseal comprising: a generally annular rigid casing having an outerperipheral wall and a radially extending side wall, which side wall isapertured for the accommodation of a shaft therethrough and is providedat its inner edge with an integrally formed inturned flange whichextends axially within the casing in substantially spaced relation tothe outer wall; a flexible annular packing within said casing having ashaft-engaging section at one end and an outwardly oilset section at theother end telescopically connected with said flange; and a separaterigid ring structure which is positioned in radially clamped engagementwith said outwardly ofi'set section of the packing at a point directlyopposite said inturned flange, on the opposite side of the packing fromsaid flange, thereby fixedly holding and sealing said outwardly ofl'setsection with said flange.

JOHN C. OLSEN.

